@side/jest-runtime

Custom runtime for Jest which addresses memory leak when using Typescript

NOTE This package was intentionally left as JS instead of being converted to TS because it is only a slight modification of existing Jest code based on this PR

Install SWC if you haven't already @swc/core @swc/jest

Make sure to configure SWC if you haven't already:

{
   "jsc": {
      "parser": {
         "syntax": "typescript",
         "decorators": true
      },
      "transform": {
         "legacyDecorator": true,
         "decoratorMetadata": true
      }
   }
}

Install custom runtime: yarn add @side/jest-runtime

Use within jest.config.js:

module.exports = {
  transform: {
    '^.+\\.ts$': '@swc/jest',
  },
  runtime: '@side/jest-runtime',
};

Why?

We were seeing memory leaks using ts-jest with node >16.10. When investigating solutions this PR fixing the issue was noticed. Since it hasn't been merged, and we still wanted to share this logic, we created this lib.

reside-eng/jest-runtime

@side/jest-runtime

Why?